path: root/libsolidity/inlineasm/AsmAnalysis.cpp

/*
    This file is part of solidity.

    solidity is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    solidity is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with solidity.  If not, see <http://www.gnu.org/licenses/>.
*/
/**
 * Analyzer part of inline assembly.
 */

#include <libsolidity/inlineasm/AsmAnalysis.h>

#include <libsolidity/inlineasm/AsmData.h>

#include <libsolidity/interface/Exceptions.h>
#include <libsolidity/interface/Utils.h>

#include <boost/range/adaptor/reversed.hpp>

#include <memory>
#include <functional>

using namespace std;
using namespace dev;
using namespace dev::solidity;
using namespace dev::solidity::assembly;


bool Scope::registerLabel(string const& _name)
{
    if (exists(_name))
        return false;
    identifiers[_name] = Label();
    return true;
}

bool Scope::registerVariable(string const& _name)
{
    if (exists(_name))
        return false;
    identifiers[_name] = Variable();
    return true;
}

bool Scope::registerFunction(string const& _name, size_t _arguments, size_t _returns)
{
    if (exists(_name))
        return false;
    identifiers[_name] = Function(_arguments, _returns);
    return true;
}

Scope::Identifier* Scope::lookup(string const& _name)
{
    if (identifiers.count(_name))
        return &identifiers[_name];
    else if (superScope && !closedScope)
        return superScope->lookup(_name);
    else
        return nullptr;
}

bool Scope::exists(string const& _name)
{
    if (identifiers.count(_name))
        return true;
    else if (superScope)
        return superScope->exists(_name);
    else
        return false;
}

AsmAnalyzer::AsmAnalyzer(AsmAnalyzer::Scopes& _scopes, ErrorList& _errors):
    m_scopes(_scopes), m_errors(_errors)
{
    // Make the Solidity ErrorTag available to inline assembly
    m_scopes[nullptr] = make_shared<Scope>();
    Scope::Label errorLabel;
    errorLabel.id = Scope::Label::errorLabelId;
    m_scopes[nullptr]->identifiers["invalidJumpLabel"] = errorLabel;
    m_currentScope = m_scopes[nullptr].get();
}

bool AsmAnalyzer::operator()(assembly::Literal const& _literal)
{
    if (!_literal.isNumber && _literal.value.size() > 32)
    {
        m_errors.push_back(make_shared<Error>(
            Error::Type::TypeError,
            "String literal too long (" + boost::lexical_cast<std::string>(_literal.value.size()) + " > 32)"
        ));
        return false;
    }
    return true;
}

bool AsmAnalyzer::operator()(FunctionalInstruction const& _instr)
{
    bool success = true;
    for (auto const& arg: _instr.arguments | boost::adaptors::reversed)
        if (!boost::apply_visitor(*this, arg))
            success = false;
    if (!(*this)(_instr.instruction))
        success = false;
    return success;
}

bool AsmAnalyzer::operator()(Label const& _item)
{
    if (!m_currentScope->registerLabel(_item.name))
    {
        //@TODO secondary location
        m_errors.push_back(make_shared<Error>(
            Error::Type::DeclarationError,
            "Label name " + _item.name + " already taken in this scope.",
            _item.location
        ));
        return false;
    }
    return true;
}

bool AsmAnalyzer::operator()(FunctionalAssignment const& _assignment)
{
    return boost::apply_visitor(*this, *_assignment.value);
}

bool AsmAnalyzer::operator()(assembly::VariableDeclaration const& _varDecl)
{
    bool success = boost::apply_visitor(*this, *_varDecl.value);
    if (!m_currentScope->registerVariable(_varDecl.name))
    {
        //@TODO secondary location
        m_errors.push_back(make_shared<Error>(
            Error::Type::DeclarationError,
            "Variable name " + _varDecl.name + " already taken in this scope.",
            _varDecl.location
        ));
        success = false;
    }
    return success;
}

bool AsmAnalyzer::operator()(assembly::FunctionDefinition const&)
{
    // TODO - we cannot throw an exception here because of some tests.
    return true;
}

bool AsmAnalyzer::operator()(assembly::FunctionCall const&)
{
    // TODO - we cannot throw an exception here because of some tests.
    return true;
}

bool AsmAnalyzer::operator()(Block const& _block)
{
    bool success = true;
    auto scope = make_shared<Scope>();
    scope->superScope = m_currentScope;
    m_scopes[&_block] = scope;
    m_currentScope = scope.get();

    for (auto const& s: _block.statements)
        if (!boost::apply_visitor(*this, s))
            success = false;

    m_currentScope = m_currentScope->superScope;
    return success;
}